Known as an example of techniques relating to this kind of field is an undershirt disclosed in Patent Literature 1. This conventional undershirt uses three kinds of materials having different tightening forces, in which the material having the highest tightening force is applied to at least a part of the triceps brachii muscles, the material having the lowest tightening force is applied to at least a part of the trapezius, latissimus dorsi, and deltoid muscles about shoulder blades, and a material having the middle tightening force is applied to the remaining regions. On the other hand, a shirt disclosed in Patent Literature 2, for example, uses a unidirectionally stretchable material and arranges the material such that the expanding/contracting direction varies among upper and lower parts of the back body, the front body, upper arm parts, sides to elbow parts, and sleeve parts.